Staying active as you age could help prevent Alzheimer's and dementia.
University of California researchers reported that seniors who stay active on a daily basis have five-percent more gray matter than people who are less active. That translates into a lower risk of Alzheimer's.
Currently, more than 35 million people worldwide are living with dementia. That number is expected to double by 2030.
"People really want to know what they can do to reduce their risk of Alzheimer's disease," Dr. Cyrus Raji of the University of California in Los Angeles said. "This shows it is easier than you think."
Physical activity can be anything from raking leaves to riding a bicycle.
"Virtually all of the physical activities examined in this study are some variation of aerobic physical activity, which we know from other work can improve cerebral blood flow and strengthen neuronal connections," Raji said.
The areas of the brain that benefit from that physical activity are the ones that consume the most energy and are sensitive to damage.